For example, the following patent document 1 describes a bottle unit (c) for a ti re puncture repair kit including an extraction cap (b) attached to a mouth portion (a1) of a bottle container (a).
As shown in FIG. 7, the extraction cap (b) for use in the bottle unit (c) includes a cap body (g) and an inner lid (h). The cap body (g) includes a first flow channel (e) to take in the compressed air from a compressor (d) into the bottle container (a), and a second flow channel (f) to sequentially take out the puncture repair liquid and the compressed air from the bottle container (a) by an intake of the compressed air. The inner lid (h) is to simultaneously close the first and second flow channels (e) and (f).
Specifically, the cap body (g) includes a fitting recess portion (g1) to screw thereto the mouth portion (a1) of the bottle container (a), and a boss portion (g2) extending upward from a bottom surface of the fitting recess portion (g1). Upper opening portions (e1) and (f1) respectively for the first and second flow channels (e) and (f) are disposed on an upper surface of the boss portion (g2). The inner lid (h) integrally includes an inner lid body (ha) to fit to an outer peripheral surface of the boss portion (g2), and a plug shank portion (hb) to fit into the upper opening portion (f1).
The bottle unit (c), prior to use, is subjected to on-vehicle storage with the first and second flow channels (e) and (f) closed by the inner lid (h). At the time of a puncture repair, the extraction cap (b) in this state is to be piped to operate the compressor (d). This allows the compressed air to flow through the first flow channel (e) into the inner lid body (ha), and upon an increase in internal pressure therein, the inner lid (h) is to automatically come off to open the first and second flow channels (e) and (f).
Accordingly, the inner lid (h) does not need to come off during the storage, and needs to easily come off under the compressed air at the time of the puncture repair. It therefore becomes necessary to enhance precision in fitting dimension between the inner lid (h) and the cap body (g) to control with high precision an interlocking force between the inner lid (h) and the cap body (g).
However, according to the conventional structure, both the inner lid body (ha) and the plug shank portion (hb) are respectively subjected to fitting, and hence interlocking variations occur in both. Therefore, still higher precision is needed for the fitting dimension, thus causing a drop in yield rate and an increase in process costs for a product inspection process.
Additionally, the inner lid (h) needs simultaneous release in the fitting of the inner lid body (ha) and the fitting of the plug shank portion (hb). For example, when the plug shank portion (hb) is first about to come off to cause a gap, the compressed air in the inner lid body (ha) leaks from the gap to the second flow channel (f). Consequently, the internal pressure of the inner lid body (ha) stops increasing. On the other hand, when the inner lid body (ha) is first about to come off to cause a gap, the compressed air leaks from the gap into the bottle container (a). As a result, the pressure in the bottle container (a) increases, which reduces a pressure difference between the inside and outside of the inner lid body (ha). Accordingly in either case, the inner lid (h) does not separate from the boss portion (g2). Thus, the inner lid body (ha) and the plug shank portion (hb) need to come off simultaneously, and this also contributes to the need for high precision.